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USB Video Class Properties

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Clients of the USB Video Class can use the following video capture property sets:

PROPSETID_VIDCAP_CAMERACONTROL PROPSETID_VIDCAP_VIDEOPROCAMP Clients of the USB Video Class can make requests on filters or individual nodes. The functionality of the node-based properties is identical to that of the pre-USB Video Class filter-based properties.

To specify a node-based property, set the KSPROPERTY_TYPE_TOPOLOGY flag in the Flags member of the KSPROPERTY structure contained in the property descriptor structure—for example, KSPROPERTY_CAMERACONTROL_NODE_S.

Because clients can address multiple nodes on a single filter, the USB Video Class enables IHVs to support cameras that have multiple independently controlled lenses.

Additionally, a new property set has been defined:

PROPSETID_VIDCAP_SELECTOR The property items contained in PROPSETID_VIDCAP_SELECTOR are node-based.

Call KsSynchronousDeviceControl or DeviceIoControl to make property requests from a user-mode component. DeviceIoControl is documented in the Microsoft Windows SDK documentation.

Each of the property items contained in the four property sets above has a corresponding method in a DirectShow COM interface. For more information about the methods, see the DirectShow documentation in the Windows SDK.

USB Video Class devices can support some or all of the property sets listed above.